package com.freight.order.utils;

import java.util.HashMap;
import java.util.Map;

/**
 * 国标GPS转高德坐标系方法
 * @Author: anshen
 * @Date: 2022/6/28 17:54
 */
public class GPSCoordinateUtil {

    private static final double PI = 3.14159265358979324;
    private static final double x_pi = 3.14159265358979324 * 3000.0 / 180.0;

    public static void main(String[] args) {
        Map<String,Double> map =  gcj_encrypt(34.829445,113.561195);
        System.out.println(map.get("lat")+"----------"+map.get("lng"));
    }

    //GPS---高德
    public static Map<String,Double> gcj_encrypt(double lat, double lng){
        //判断是否是国内坐标，如果是就计算，如果不是就原样返回
        if (outOfChina(lat, lng)){

            Map<String,Double> map = new HashMap<>();
            map.put("lat",lat);
            map.put("lng",lng);
            return map;
        }
        Map<String, Double> delta = delta(lat, lng);
        Map<String,Double> map = new HashMap<>();
        Double lat1 = delta.get("lat");
        lat1 = lat - 0 + lat1;
        Double lng1 = delta.get("lng");
        lng1 = lng - 0 + lng1;
        map.put("lat",lat1);
        map.put("lng",lng1);
        return map;
    }

    public static  Map<String,Double> delta(double lat, double lng) {
        // Krasovsky 1940
        //
        // a = 6378245.0, 1/f = 298.3
        // b = a * (1 - f)
        // ee = (a^2 - b^2) / a^2;
        double a = 6378245.0; //  a: 卫星椭球坐标投影到平面地图坐标系的投影因子。
        double ee = 0.00669342162296594323; //  ee: 椭球的偏心率。
        double dLat = transformLat(lng - 105.0, lat - 35.0);//lng是x,lat是y
        double dLon = transformLng(lng - 105.0, lat - 35.0);//lng是x,lat是y
        double radLat = lat / 180.0 * PI;
        double magic = Math.sin(radLat);
        magic = 1 - ee * magic * magic;
        double sqrtMagic = Math.sqrt(magic);
        dLat = (dLat * 180.0) / ((a * (1 - ee)) / (magic * sqrtMagic) * PI);
        dLon = (dLon * 180.0) / (a / sqrtMagic * Math.cos(radLat) * PI);
        Map<String,Double> map = new HashMap<>();
        map.put("lat",dLat);
        map.put("lng",dLon);
        return map;
    }

    //判断是否是国内坐标
    public static  boolean outOfChina(double lat, double lng){
        if (lng - 72.004 < 0 || lng - 137.8347 > 0){
            return true;
        }
        if (lat - 0.8293 < 0 || lat - 55.8271 > 0){
            return true;
        }
        return false;
    }

    //lng是x,lat是y
    public static  double transformLat(double x, double y){
        double ret =  -100.0 + 2.0 * x + 3.0 * y + 0.2 * y * y + 0.1 * x * y + 0.2 * Math.sqrt(Math.abs(x));
        ret += (20.0 * Math.sin(6.0 * x * PI) + 20.0 * Math.sin(2.0 * x * PI)) * 2.0 / 3.0;
        ret += (20.0 * Math.sin(y * PI) + 40.0 * Math.sin(y / 3.0 * PI)) * 2.0 / 3.0;
        ret += (160.0 * Math.sin(y / 12.0 * PI) + 320 * Math.sin(y * PI / 30.0)) * 2.0 / 3.0;
        return ret;
    }

    //lng是x,lat是y
    public static  double transformLng(double x, double y){
        double ret = 300.0 + x + 2.0 * y + 0.1 * x * x + 0.1 * x * y + 0.1 * Math.sqrt(Math.abs(x));
        ret += (20.0 * Math.sin(6.0 * x * PI) + 20.0 * Math.sin(2.0 * x * PI)) * 2.0 / 3.0;
        ret += (20.0 * Math.sin(x * PI) + 40.0 * Math.sin(x / 3.0 * PI)) * 2.0 / 3.0;
        ret += (150.0 * Math.sin(x / 12.0 * PI) + 300.0 * Math.sin(x / 30.0 * PI)) * 2.0 / 3.0;
        return ret;
    }

}